China's defence ministry says it has opened an investigation into the country's highest-ranking general over grave violations of discipline and the law.
The ministry gave no further details about accusations against General Zhang Youxia, who has widely been seen as President Xi Jinping's closest military ally. However, in China, the accusation of wrongdoing is usually a euphemism for corruption.
In its announcement, the ministry stated that another senior military officer, General Liu Zhenli, is also under investigation.
This action follows the expulsion of nine top generals in October, marking one of the largest public crackdowns on the military in decades.
Zhang, 75, serves as a vice-chairman of the Central Military Commission (CMC) - the Communist Party group headed by President Xi which controls the armed forces. Additionally, Zhang sits on the party's top decision-making body, the 24-person Politburo.
His father was one of the founding generals of the Chinese Communist Party. Zhang, who joined the army in 1968, is among the few senior leaders with actual combat experience and was retained in office beyond the customary military retirement age, indicating President Xi's prior confidence in him.
The announcement follows rumors that Zhang and Liu could be facing an investigation, as neither was present at a high-level party event in December.
Since taking power, President Xi has initiated numerous anti-corruption drives across various sectors, recently intensifying focus on the military. Xi has referred to corruption as the biggest threat to the Communist Party, asserting that the fight against it remains grave and complex.
Some advocates argue these policies enhance governance, while critics believe they are tactics for purging political adversaries. With the new investigation into Zhang and Liu, the CMC is now left with only two members: Xi, as chairman, and Zhang Shengmin, who oversees military discipline.
